Velocity Distributions and Fluctuations in a Taylor Vortex Flow

Abstract

Velocity distributions and fluctuations in a Taylor vortex flow between concentric cylinders in which the inner cylinder rotates (a circular Coutette system) are investigated by means of a flow-visualization technique and hot-wire measurements. The experiments are performed up to Re/Re_c=10 in a system where the Reynolds number Re is slowly increased at a constant rate. It is found that both the dimensionless wavelength λ/δ and the number of travelling azimuthal waves become large as the radius ratio γ_i/γ₀ approaches 1. Wave speed decreases rapidly with an increase in Re and becomes constant: it is smaller than the fluid velocity at the mean radius. The amplitude of waves at the source is larger than that at the sink. The highest peak of the velocity power spectrum does not always correspond to the wave frequency.